[Tig] mistake in wikipedia?

[Dave Corbitt]

On Jul 14, 2007, at 10:42 AM, Kevin Shaw wrote:
>
> Hi
>
>> http://en.wikipedia.org/wiki/Color_grading#_note-filmintovideo
>
> I changed the wikipedia entry with a quick fix, but I am unsure about 
> the
> early description of a telecine.
>
> The article says that the early telecines were
>> a film projector connected to a video camera
>
> But I thought they were already using flying spot machines by the time
> television was broadcast to the public. Maybe it is a US vs UK 
> difference?
>
> Anybody know more about the what went on?
> Thanks,
> Kevin
>
> Kevin Shaw                 colorist, instructor and consultant
> kevs at finalcolor.com          www.finalcolor.com
> ----------------------------------------------

Hi Kevin,

Since the US was a 30 frames/60 fields per second video standard 
country and
film was 24 fps, using flying spot was impractical until the advent of 
digital signal
processing in the mid to late 1970's. In the UK, it was relatively easy 
to use flying
spot since the film was run at 25 fps and the scanner ran at 25 
frames/50 fields.
No 2:3 pulldown or complex jumpscan pattern to adjust. Jump scan would 
have
had to be used for flying spot since image storage was not possible 
without
digital memory, etc. Cintel did try to market their Jump Scan Mark III 
in the US
in the mid 70's but the flicker and field registration problems made it 
a lot less
than favorable in broadcasters eyes. Constant tweaking was necessary to
minimize image flicker and twitter caused by the interaction of film 
shrinkage
and the finite positioning of the multiple patches necessary to scan 
the film images.

Post Production was in its infancy at that time. Early broadcasting 
preceded
videotape so many early programs were transmitted from a live on-air 
telecine
and the very early ones used B&W image iconoscope cameras to sense an
image projected directly from a film projector down the camera lens 
barrel.

When color came in the mid 1950's, telecines in the US had 3 or 4 tube 
vidicon
cameras as the image sensors. 4 tube cameras used a separate sensor for
Luminance, then three for RGB color difference. When I started in this 
business
back in 1974 at Teletronics in New York, we had a GE film chain 
incorporating
a pedestal GE telecine video camera with vidicons. A Simplex projector 
was
used for 35mm print film and an RCA projector (I think) was used for 16 
mm.
A powered switchable mirror system called a Multiplexer, directed the 
light
from those two projectors or a third, a slide projector, down the lens 
barrel of
the camera. We added foil tabs to the film to mark events and that 
triggered a
bunch of relays that switched in banks of multi turn pots to control 
color timing.
Primitive, but it worked. By 1976, we had graduated to RCA TK-26 
telecines,
still using vidicon sensors. The images were laggy, soft, had color 
registration
errors, colorimetry errors, and generally looked like cr at p but it was 
"state of the art".
When Cintel showed their Mark III at the NAB in 1976, it was a 
revelation to
someone me who was fed up with the compromised image quality of vidicon
based telecines. Images were amazingly sharp with much improved color.
Film grain became visible, something you would never see on a vidicon 
telecine
because it was too soft. The real time instant scanning aspect for the 
first time
allowed people (in the US) to see film on a video monitor that actually 
looked
like film, not a blurry smeary laggy mess. But the "not invented here" 
syndrome
kept many on this side of the Atlantic from jumping on board what was
eventually to become the state of the art in the late 70's and 80's. 
Once Digiscan
was released, vidicon based telecines were dead, almost overnight. The 
digital
storage of Digiscan allowed the telecine to scan each from only once 
with a
progressive raster so all the flicker issues and field registration 
issues
disappeared and made flying spot a real and practical solution to
improved image quality.

Sorry for getting a little long winded on this one.

Dave Corbitt
FrontNICHE North America
Eastern Sales Manager
Summit, NJ 07901
email  dcorbitt at frontnichena.com
http://www.frontnichena.com/